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%I #6 Aug 08 2015 22:28:36
%S 1,1,4,1,6,1,720,90,10,1,12,1,3360,240,16,1,18,1,9240,462,22,1,
%T 11793600,491400,19656,756,28,1,30,1,45239040,1413720,42840,1260,36,1,
%U 59280,1560,40,1,42,1,91080,2070,46,1,311875200,6497400,132600,2652
%N Product of all composite numbers k such that n<k<prime(r) where prime(r-1)<=n, or 1 if this set of k is empty.
%C All terms that differ from 1 have the format A092435(i+1)/A092435(i). - _R. J. Mathar_, Aug 15 2007
%e a(7) = 8*9*10 = 720.
%p A109915 := proc(n) local a,rm1,k; a := 1: rm1 := numtheory[pi](n) ; for k from n+1 to ithprime(rm1+1) do if not isprime(k) then a := a*k; fi; od: RETURN(a) ; end: seq(A109915(n),n=1..50) ; # _R. J. Mathar_, Aug 15 2007
%Y Cf. A109914.
%K nonn
%O 1,3
%A _Amarnath Murthy_, Jul 16 2005
%E Corrected and extended by _R. J. Mathar_, Aug 15 2007